Assume I am standing in a desert at night (It's pitch dark). I have an opaque white object in front of me inclined at 45 degrees (see diagram). I now turn on a point light source next to me. http://img199.imageshack.us/img199/8945/lightt.jpg [Broken] When I imagine the scene I feel I will be able to see point P on the object in front of me, at least a certain shade of white (grayish). However, when I think of this from a physics point of view, there is no ray of light from the light source that hits point P and then reflects to my eye (considering angle of incidence = angle of reflection). When I trace the ray from the eye to point P and toward the reflecting source I seem to go to inifnity (there is no wall there to reflect any light as it is a desert). So in reality will any shade of white on point P be visible to the observer? If yes, then which ray of light does it come from and how does it reach the eye?